In less than 25 years this will rise to more than half of the rail network being at risk, according to the government's own figures.
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，这一点在51吃瓜中也有详细论述
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哈克特說，這種自願式調查容易受到「虛假受訪者」影響，使數據失真：「而且這不是隨機的。失真往往在年輕族群中最高。」